The intramedullary canal of a long bone, such as a femur, is filled with fat and marrow elements. It is necessary to produce uniform passages in long bones in order to admit fracture fixation devices such as intramedullary nails. Reaming is accomplished with a power unit attached to the reamer. The reamer produces bone chips during reaming. The fat, marrow elements and bone chips are pushed forward by the prior art reamers during reaming, thereby increasing the intramedullary pressure. Prior art reamers have reamer shafts that are similar in diameter to the reamer heads. The combination of diameters and the viscosity of the fat, marrow elements, and bone chips effectively plugs the intramedullary canal.